Issue #1404 Durability test which checks that after restore DB can be used without any issues was added.
Issue #1404 Shadow copy of paginated cluster state was implemented.
Issue #1404 Record creation crash test was passed.
Issue #1404  Document update crash tests were passed.
Issue #1404  Document update+create+delete crash test was passed.
Issue #1404  WAL performance improvements.
Issue #1404  Crash test with creation of big data records with small cache size was passed.
Issue #1404  Storage keep open is set to true by default for embedded DB.
Merge remote-tracking branch 'origin/develop' into plocal-crash-test

Conflicts:
	core/src/main/java/com/orientechnologies/orient/core/config/OGlobalConfiguration.java
	graphdb/src/test/java/com/orientechnologies/orient/graph/blueprints/RemoteGremlinTest.java
Issue #1404 Import/export functionality was restored.
Issue #1404 WAL durability during power failure was improved.
Issue #1404 New paginated cluster attributes were added.
Issue #1404. Support for plocal in remote server was added. plocal is default storage type for remote tests.
Merge branch 'plocal-crash-test' into develop

Conflicts:
	client/src/main/java/com/orientechnologies/orient/client/remote/OStorageRemote.java
	server/src/main/java/com/orientechnologies/orient/server/journal/ODatabaseJournal.java